Real world data supports InterMune's IPF drug

New pooled analyses of data from phase 3 trials presented by InterMune shows that its treatment for idiopathic pulmonary fibrosis (IPF) pirfenidone has long-lasting benefits for patients.

The data comes ahead of the most decisive moment in InterMune's history, as it awaits an FDA ruling on the drug.

The new analyses was based on data from three separate phase 3 trials, and looked at multiple measures of disease status in patients who continued taking the treatment for up to 72 week. Professor Paul W. Noble, M.D. from the Cedars-Sinai Medical Center, Los Angeles, presented the data at the European Respiratory Society Annual Congress, currently underway in Berlin.

InterMune is entering a new phase in its development – it recently re-submitted pirfenidone with the FDA, and has also just agreed to be bought by Swiss pharma giant Roche for $8.3 billion. Pirfenidone has been approved in Europe since 2011, where it is known as Esbriet, but has been locked out of the US market because of FDA doubts about its data.

InterMune filed its new data with the FDA in May, which then promptly granted it 'Breakthrough' status in July. However a new rival treatment, in the shape of Boehringer Ingelheim's nintedanib is now neck-and-neck with pirfenidone in the race for approval. Boehringer's drug gained the same Breakthrough status a day ahead of pirfenidone, meaning that if both are approved, they could reach the market almost simultaneously.

InterMune has already submitted the data from the phase 3 trials to the FDA, but the new pooled analysis, plus results from real world studies, are building a stronger case for pirfenidone in its coming battle with nintedanib.

Analyses of pooled outcomes at the time of the study primary endpoint, in which patients were treated for 52 weeks in ASCEND and 72 weeks in CAPACITY, show a 52% reduction in the risk of a ≥10% decline in percent predicted forced vital capacity (FVC) or death (hazard ratio [HR] 0.48; 95% confidence interval [CI] 0.37–0.63, p<0.001).

The analyses also show a 34% reduction in the risk of a ≥50m decline in 6-minute walk distance (6MWD) or death (HR 0.66; 95% CI 0.54–0.82, p<0.001), and the progression-free survival analysis showed the risk of disease progression was reduced by 38% (HR 0.62; 95% CI 0.52–0.75, p<0.001) in the pirfenidone group compared with placebo.

The risk of all-cause mortality was reduced by 37% (HR 0.63; 95% CI 0.41–0.98, p=0.040) and the risk of treatment emergent IPF-related mortality was reduced by 60% (HR 0.40; 95% CI 0.20–0.80, p=0.007) in the pirfenidone group compared with placebo. The risk of a ≥20 point increase in UCSD SOBQ score or death (HR 0.75; 95% CI 0.60–0.93, p=0.007) was decreased by 25% at study endpoint.

Paul Noble, Cedars-Sinai Medical Center, Los Angeles, said, "IPF is a chronic, progressive, and irreversible lung disease that requires both urgent and long-term clinical management. This analysis provides compelling evidence to support the long-term efficacy benefits associated with pirfenidone. Coupled with the long-term safety data presented at this meeting, these results will further inform clinical decision making by healthcare practitioners involved in the care of patients with IPF."

Real world data

Data from two further 'real world' trials support InterMune's case for the safety and efficacy of its lead drug.

A study presented by Professor Ulrich Costabel M.D. from Essen University Hospital in Germany examined the long-term safety of pirfenidone in patients with IPF enrolled in the RECAP study, a long-term, open-label extension study evaluating continued therapy with pirfenidone in patients who completed one of the Phase 3 trials.

Interim analysis of data from this ongoing trial showed that long-term treatment with pirfenidone has a favourable safety profile and is generally well tolerated for up to 4.9 years. The type and frequency of adverse events were consistent with the Phase III trials, as well as the recently presented comprehensive safety analysis in the integrated population from four clinical trials that included patients with up to 8.6 years of exposure to pirfenidone.

Finally, an interim analysis of data from 530 patients enrolled in the PASSPORT study, a post-authorisation surveillance study looked at the long-term safety of patients receiving pirfenidone in the clinical setting in Europe. The interim results, presented by Dirk Koschel M.D. of Fachkrankenhaus Coswig in Germany, showed that the safety of pirfenidone in the real-world setting appears to be consistent with that observed in clinical trials. In this ongoing, observational, prospective, patient registry, pirfenidone was shown to have a favourable safety profile and was generally well tolerated.